This invention relates to cut-resistant yarns, particularly composite cut resistant yarns which have been treated to retard the growth of microbes which can cause food contamination and illness in humans and to garments such as cut-resistant gloves knitted or woven from such yarns. In accordance with the invention, yarns treated to retard the growth of microbes, such as bacteria, molds and fungi are knitted or woven into gloves of the type worn by meat cutters and others whose job involves working with knives, saws and other sharp objects.
Certain types of medical gloves treated with antimicrobial agents are known, as are cut-resistant gloves which achieve a measure of antimicrobial protection through the plating of a treated acetate fiber to a cut-resistant yarn as a part of the knitting process. However, applicants are not aware of a cut-resistant composite yarn which itself contains an antimicrobial component.
Users needing protection against cuts and also requiring a high level of dexterity now have a variety of products available for use. Some such products, for example, gloves knitted from fibers such as those sold under the name KEVLAR and ultrahigh molecular weight polyolefin fibers such as those sold under the name SPECTRA, provide a moderate degree of safety and protection but are extremely costly. Commercial examples of these engineered fibers include those sold by Honeywell, Inc. under the names SPECTRA 900 and SPECTRA 1000, and by the DuPont company of Wilimington, Del. under the name KEVLAR.
Less expensive yarns have been developed from various combinations of wire, fiberglass, polyester, polypropylene and polyolefin fibers which are nevertheless more cut-resistant. Several, embodiments are disclosed in the following patents:
U.S. Pat. No. 4,384,449 shows protective gloves and the like and a yarn comprising a core of a flexible wire alongside an aramid fiber strand or strands and a covering of aramid fiber such as that manufactured and sold under the name KEVLAR by the DuPont company of Wilmington, Del. in which the aramid fiber is either spun or filament. Two aramid fiber strands, either spun or filament, are wrapped around the core with one strand wrapped in a clockwise direction and the other strand wrapped in a counter-clockwise direction with the opposite spiral wrapping of the strands serving to secure the strands in position on the core without any other securing means. The yarn having a flexible core with aramid fiber strands wrapped thereon is used to make protective gloves on conventional glove knitting or weaving machinery and is capable of movement in relation to needle eyes and the like without jamming in the same manner as various natural and synthetic fiber yarns. The yarn having a flexible core with aramid fiber strands wrapped thereon is also used in making various U.S. other products normally made of conventional fiber yarn.
U.S. Pat. No. 4,651,514 shows an electrically non-conductive, cut and abrasion resistant yarn for use in the manufacture of protective coverings including a core of monofilament nylon having a diameter in the range of about 0.004 to 0.020 inches, a first wrap on the core of at least one strand of aramid fiber having a cotton count size in the range of about 1/1 to 30/1 and a second wrap on the core of texturized nylon of two to eight ply construction. Each ply is made up. of 24 to 44 nylon filaments with each filament being about 50-90 denier.
U.S. Pat. No. 4,777,789 shows an improved yarn, fabric and protective garment made from such yarn where the yarn, fabric and garment exhibit increased cut resistance. The yarn includes a cord made of fiber and a covering wrapped around the core, the covering includes at least one strand of wire wrapped around the core.
U.S. Pat. No. 4,818,587 shows nonwoven fabrics contain at least 30% by weight of heat-adhesive composite fibers consisting of core portion and sheath portion, the core portion being of the side-by-side type composite structure comprising two core components of different polypropylene base polymers in a composite ratio of 1:2 to 2:1, one of the core components having a Q value, expressed in terms of the weight-average molecular weight/the number-average molecular weight, equal to or higher than 6 and the other having a Q value equal to or lower than 5, and the sheath portion meeting at least the requirement that it should comprise a sheath component of a polyethylene base polymer having a melting point lower by at least 20xc2x0 C. than the lower one of the melting points of the two core components. The nonwoven fabrics are bulky and soft due to the crimps of the heat-adhesive composite fibers resultant form the core portion and are stabilized by the interfiber bonds of the sheath portion.
U.S. Pat. No. 4,838,017 shows an improved yarn, fabric and protective garment made from such yarn where the yarn, fabric and garment exhibit increased cut resistance. The yarn includes a core made of fiber and a covering wrapped around the core, the covering includes at least one strand of wire wrapped around the core.
U.S. Pat. No. 4,886,691 shows a cut resistant article comprising a cut resistant jacket surrounding a less cut resistant member. The jacket comprises a fabric of yarn and the yarn consists essentially of a high strength, longitudinal strand having a tensile strength of at least 1 GPa. The strand is wrapped with another fiber or the same fiber.
U.S. Pat. No. 4,936,085 shows an improved yarn, fabric and protective garment made from such yarn, where the yarn, fabric and garment exhibit increased cut resistance, flexibility, pliability and softness. The yarn is non-metallic and includes a core made of fiber and a covering wrapped around the core. At least one of the strands is fiberglass, the non-fiberglass strands are preferably nylon or polyester.
U.S. Pat. No. 5,010,723 shows a yarn produced from two or more twisted cellulosic fibers, such as cotton or cotton rayon fibers, the plies being helically wound around a thermoplastic filament core which is subsequently melted to bind the inner portions of the yarn together so that it does not untwist or shed lint readily. The yarn is employed in a dust mop or floor mat for a shampoos, bonnet for stain resistant treated carpet.
U.S. Pat. No. 5,119,512 shows a cut resistant article 20 comprising a cut resistant jacket surrounding a less cut resistant member. The jacket comprises a fabric of yarn and the yarn consists essentially of a high strength, longitudinal strand having a tensile strength of at least 1 GPa. The, strand is wrapped with another fiber or the same fiber. In another embodiment, the invention is a highly cut resistant yarn of at least two nonmetallic fibers. One fiber is inherently cut resistant like high strength polyethylene, polypropylene or aramids. The other fiber in the yarn has a high level of hardness.
U.S. Pat. No. 5,177,948 shows an improved non-metallic yarn, 30 fabric and protective garment made from such yarn, where the yarn, fabric and garment exhibit increased cut resistance, flexibility, pliability and softness. The yarn is non-metallic and includes a core made of fiber and a covering wrapped around the core. At least one of the strands of the core is fiberglass, the non-fiberglass strands are preferably nylon, extended chain polyethylene, aramid or polyester.
Any of these structures can be treated in accordance with the invention of this application in order to provide antimicrobial effects to the yarn and the garment fabricated from the yarn. These yarns are generally sufficiently heat-resistant to permit periodic sterilization to kill bacteria and other microbes. Yarns treated as described in this application provide greatly retarded microbe development between sterilization treatments, thereby greatly reducing the possibility of contamination of food products.
Therefore, it is an object of the invention to provide a cut-resistant composite yarn which has been treated to provide antimicrobial effects.
It is another object of the invention to provide a cut-resistant composite yarn which has at least one carrier yarn which has been treated to provide antimicrobial effects.
It is another object of the invention to provide a cut-resistant composite yarn which is sufficiently flexible and resilient to be woven or knitted into a garments having antimicrobial effects.
The present invention provides significant protection both against cuts to the user but also retards growth of microbes which can contaminate food products being processed or handled by the user.
Typically, the core material is a strand of fiberglass. In order to minimize the mount of fiberglass fragments that break free from the fiberglass strand and irritate the skin of the person coming in contact with the fiberglass fragments, a series of covering wraps are employed. These covering wraps may also be a highly cut resistant material in and of themselves. In addition, the outer wrap may be a fiber that is smooth to the touch such as polyester or nylon. However, in order to maximize cut resistance, the covering wraps may be selected from the group consisting of polyolefins such as that sold under the name SPECTRA or aramids such as that sold under the name KEVLAR.
Preferably, the cover members are wrapped, wound or twisted around the core in a manner which permits successive layers to be wrapped, wound or twisted around the core in an opposite direction from the cover element immediately below.
The resulting protective yarns are then suitable for knitting into protective gloves and other protective garments. These yarns offer an inexpensive alternative to existing protective yarns while providing substantial cut protection without irritating a user""s skin.
Winding the cover layers on the fiberglass core so that an adjacent cover layer is wound in a direction opposite to the layer immediately beneath it gives the protective yarn the desired characteristics at a much lower cost than existing yarns. The invented protective yarn is flexible enough that it can be knitted into a protective fabric or garment on conventional knitting or weaving-machines and yet is strong enough to offer substantial cut resistance. Finally, the invented protective, yarn resists shrinkage which results from exposure to extremely high temperatures during the washing process.
These and other objects of the present invention are achieved in the preferred embodiments disclosed below by providing an antimicrobial, cut-resistant composite yarn, comprising a core member including at least one cut-resistant strand, a cover member including at least one strand wrapped around and enclosing the core member, wherein at least one strand in either the core member or the cover member is treated with and incorporates an antimicrobial compound.
According to one preferred embodiment of the invention, the core member comprises a cut-resistant strand and a synthetic core yarn, wherein the synthetic core yarn is treated with and incorporates the antimicrobial compound.
According to another preferred embodiment of the invention, the cover member comprises at least two oppositely-wrapped synthetic cover yarns, wherein at least one of the synthetic cover yarns is treated with and incorporates the antimicrobial compound.
According to yet another preferred embodiment of the invention, the synthetic core yarn and the synthetic cover yarns are selected from the group consisting of polyester, polyethylene, polypropylene, nylon and acetate.
According to yet another preferred embodiment of the invention, an antimicrobial, cut-resistant composite yarn is provided, comprising a core member including at least one cut-resistant strand and at least one synthetic yarn residing in substantially parallel relation to each other, a cover member including at least two synthetic yarns wrapped in opposite directions around and enclosing the core member, wherein at least one yarn in either the core member or the cover member is treated with and incorporates an antimicrobial compound.
According to yet another preferred embodiment of the invention, the cut-resistant strand is selected from the group consisting of fiberglass, metal wire, aramid and polyolefin fiber.
According to yet another preferred embodiment of the invention, the cover member comprises three yarns wrapped in alternate directions around the core member.
According to yet another preferred embodiment of the invention, the cut-resistant composite yarn including a core wrapper strand wrapped around the core member between the core member and the cover member.
According to yet another preferred embodiment of the invention, the core wrapper strand is chosen from the group consisting of fiberglass, metal wire, aramid and polyolefin fiber.
According to yet another preferred embodiment of the invention, an antimicrobial, cut-resistant composite yarn is provided, comprising a core member including a cut-resistant strand and a synthetic yarn residing in substantially parallel relation to each other, a core wrapper strand wrapped around the core member, and comprising a strand chosen from the group consisting of fiberglass, metal wire, aramid and polyolefin fiber, a cover member including three synthetic yarns wrapped in alternating directions around and enclosing the core member, wherein at least one yarn in the cover member is treated with and incorporates an antimicrobial compound.
According to yet another preferred embodiment of the invention, a cut-resistant garment is provided which is fabricated from an antimicrobial, cut-resistant composite yarn according to the invention.
According to yet another preferred embodiment of the invention, the garment comprises a glove.
According to yet another preferred embodiment of the invention, the glove is fabricated by knitting.
In one preferred embodiment of the present invention, a protective yarn has a single fiberglass core fiber and one or more cover members. The cover members are selected from the group consisting of aramid fiber, ultrahigh molecular weight polyolefin fiber, polyester, nylon and polyacrylic fibers. The cover members are wrapped, wound or twisted around the core in a manner which permits successive layers to be wrapped, wound or twisted around the core in an direction opposite that of the cover member immediately below.
By using only one fiberglass core instead of multiple non-glass fiber cores, the present invention provides cut resistance equal to or greater than that obtained by using purely engineered cut resistant fibers such as those sold under the names SPECTRA and a KEVLAR at a significantly lower cost. Substituting a lower strength hard and brittle fiber material such as fiberglass to the core of the yarn adds a significant level of cut resistance at a fraction of the cost. The addition of new yarn components has substantially reduced a user""s manual dexterity problems and increased the protection against cuts to the protected body member.